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GSM 900 MHz radiation inhibits ants' association between food sites and encountered cues

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The kinetics of the acquisition and loss of the use of olfactory and visual cues were previously obtained in six experimental colonies of the ant Myrmica sabuleti meinert 1861, under normal conditions. In the present work, the same experiments were conducted on six other naive identical colonies of M. sabuleti, under electromagnetic radiation similar to those surrounding GSM and communication masts. In this situation, no association between food and either olfactory or visual cues occurred. After a recovery period, the ants were able to make such an association but never reached the expected score. Such ants having acquired a weaker olfactory or visual score and still undergoing olfactory or visual training were again submitted to electromagnetic waves. Not only did they lose all that they had memorized, but also they lost it in a few hours instead of in a few days (as under normal conditions when no longer trained). They kept no visual memory at all (instead of keeping 10% of it as they normally do). The impact of GSM 900 MHz radiation was greater on the visual memory than on the olfactory one. These communication waves may have such a disastrous impact on a wide range of insects using olfactory and/or visual memory, i.e., on bees.
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GSM 900 MHz radiation inhibits ants’ association
between food sites and encountered cues
Marie-Claire Cammaerts
1
, Philippe De Doncker
2
, Xavier Patris
2
,
Franc¸ois Bellens
2
, Zoheir Rachidi
1
& David Cammaerts
1
1
Universite
´Libre de Bruxelles, Faculte
´des Sciences, Bruxelles, Belgium, and
2
Universite
´
Libre de Bruxelles, Faculte
´des Sciences Applique
´es, Bruxelles, Belgium
The kinetics of the acquisition and loss of the use of olfactory and visual cues were previously
obtained in six experimental colonies of the ant Myrmica sabuleti MEINERT 1861, under normal
conditions. In the present work, the same experiments were conducted on six other naive
identical colonies of M. sabuleti, under electromagnetic radiation similar to those surrounding
GSM and communication masts. In this situation, no association between food and either
olfactory or visual cues occurred. After a recovery period, the ants were able to make such an
association but never reached the expected score. Such ants having acquired a weaker olfactory
or visual score and still undergoing olfactory or visual training were again submitted to
electromagnetic waves. Not only did they lose all that they had memorized, but also they lost it in
a few hours instead of in a few days (as under normal conditions when no longer trained). They
kept no visual memory at all (instead of keeping 10% of it as they normally do). The impact of
GSM 900 MHz radiation was greater on the visual memory than on the olfactory one. These
communication waves may have such a disastrous impact on a wide range of insects using
olfactory and/or visual memory, i.e., on bees.
Keywords Ant, Colony collapse disorder, Food collection, Myrmica sabuleti, Olfactory memory,
Visual memory
INTRODUCTION
Many insects, e.g., ants and bees, can be conditioned using classical conditioning
(Cammaerts, 2004b,c) or operant conditioning (Cammaerts, 2004d). We used such
(classical and operant) conditioning as a method to study Myrmica sabuleti Meinert
1861 workers’ visual perception (Cammaerts, 2004a, 2007a,b, 2008). We then studied
this ant species’ use of vision and olfaction for foraging (Cammaerts and Lambert,
2009, Cammaerts and Rachidi, 2009). Based on the results, we suspected that
Myrmica sabuleti workers’ associate food sites and either olfactory or visual cues
differently. We therefore analyzed these types of associations, focusing, among
others, on their kinetics (Cammaerts et al., in press). Working on six colonies, we
found that olfactory conditioning was acquired in 4 days reaching then a score of
8085% while visual conditioning was acquired in 6 7 days reaching then a score of
7580% (Fig. 1, left part). When training was stopped, olfactory conditioning, since
Address correspondence to Marie-Claire Cammaerts, Universite
´Libre de Bruxelles, Faculte
´des
Sciences, DBO, CP 160/12, 50 Av. F. Roosevelt, 1050 Bruxelles, Belgium; E-mail: mtricot@ulb.ac.be
Electromagnetic Biology and Medicine, Early Online: 1–15, 2012
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ISSN: 1536-8378 print / 1536-8386 online
DOI: 10.3109/15368378.2011.624661
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that time, decreased entirely in 3.5 days while visual conditioning, after some delay,
decreased during 4 5 days reaching the never lost score of 60 70% (Fig. 1, right
part). This provided a basis for studying the effect of GSM 900 MHz radiation on
animals learning or conditioning.
Gould (1982) wrote: ‘During the short-term phase of active neural processing,
any shock or disturbance is likely to cause to forget what is just experienced’. We
therefore intended to study the impact of GSM 900 MHz radiation on naive ants’
association between food and olfactory or visual cues, suspecting some negative
effect of these communication waves during the process of conditioning.
Anyone can now find, on the Internet, plenty of links providing information about
potential dangers of mobile phone radiation. Balmori (2009) clearly explained the
possible impact of communication waves on the world life. Such probable effects
may also be relevant for insects, essentially for those which live dependent on
learning and memory. Bees are such insects. In the “Conclusions” section below, at
page 13, we report on works which reveal and examine the effects of electromagnetic
(especially RF) radiation on bees (i.e., Sharma and Kumar, 2010; Kumar et al., 2011).
The current worldwide decline of this Hymenoptera (Guillet, 2007) increased our
aim to study the impact of electromagnetic waves on ants’ olfactory and visual
conditioning (so too, on their use of encountered cues), a study we could precisely
make since we knew exactly the kinetics of these conditionings under normal
condition (Fig. 1).
MATERIAL AND METHODS
Collection and Maintenance of Ants
The assays were conducted on six large naive colonies collected in two abandoned
quarries located in the Aise valley and at Lingle
´(Ardenne, Belgium).
A colony of M. sabuleti contains one or several queens, brood (eggs, larvae, and
nymphs according to the season), and several hundred workers. Most of the workers
stay in the nest, taking care of the queens and the brood. Several workers stay at the
nest entrances. Rather old workers (1050) forage outside, collect food, go back to
FIGURE 1 Acquisition (left graphs) and loss (right graphs) of olfactory (¼squares) and visual
(¼circles) conditioning. Ants of six colonies were collectively trained and individually tested in the
course of time, day (white parts, empty squares and circles) and night (grey parts, black filled
squares and circles) under normal condition (i.e., with no GSM 900 MHz radiation). Olfactory
conditioning ended after 130 h. There is no gap between acquisition and loss. Myrmica sabuleti
workers lose an olfactory conditioning more rapidly than a visual one.
2 M.-C. Cammaerts et al.
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their nest, and recruit nestmates toward food sites. To do so, they use their trail
pheromone and their area marking substances as well as encountered olfactory and
visual cues. Foragers must thus be able to learn such cues. Note that each ant species
has its own characteristics, life cycle, population structure, and navigation system.
Here, we only briefly describe the social life of M. sabuleti.
In the present work, the experimental colonies used were demographically
similar, each containing a queen, brood, and about 500 workers. They were labeled
16. Nymphosis began in colony 2 at the start of the present work. The colonies were
maintained in the laboratory in artificial nests made of one to three glass tubes half-
filled with water, a cotton-plug separating the ants from the water. The glass tubes
were deposited in trays (37 cm £52 cm £8 cm) whose borders were covered with
talc (Fig. 2). The trays served as foraging areas: food was delivered in them and ants
were trained as well as tested in appropriate apparatus positioned on the floor of the
trays (Fig. 4) but having their own, not chemically marked bottom.
The temperature was maintained ca. 208^28C and humidity at about 80%, both
optimal values for the studied species. Lighting intensity was ca. 600 lux during the
training phases and 10,000 lux while feeding and testing the ants.
A saturated solution of brown sugar was permanently offered in a glass tube
plugged with cotton. Pieces of dead cockroaches were provided twice a week,
deposited on a piece of glass. This meat food was not provided during experiments
because it served as a reward during training (Fig. 2, 4).
GSM 900 MHz Exposure Set-up
The radio frequency (RF) signal was produced by a Rohde and Schwarz dual-
channel SMATE200A vector signal generator (Fig. 2). The frequency was set to
FIGURE 2 Experimental design used for conducting olfactory (A, C) and visual (B, D) conditioning
under GSM 900 MHz radiation. Six large colonies were positioned on the right and on the left of a
wave generator, under two duly oriented antennae fixed on the wall. Fennel was used for olfactory
conditioning (A, C), green hollow cubes for visual conditioning (B, D), and pieces of dead
cockroaches as a reward.
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900 MHz, which is typical for GSM communications, and the signal was GSMK
modulated in accordance to the GSM standard. The signal was produced via two
channels, each of which delivered electromagnetic waves to three nests (Fig. 2). The
two series of three nests were exposed to the waves by means of omni-patch
antennas (one antenna connected to each channel of the source) with horizontal
polarization and gain about 1.6. The antenna was placed one meter above the ants
(Fig. 2). This experimental set-up was chosen to give an almost uniform electrical
field pattern over the nests. The source power was set to 10 dBm (¼dBmW ¼power
ratio in decibels (dB) of the measured power referenced to one milliwatt (mW), a
convenient measure of absolute power) for each channel, theoretically giving a
nominal electric field value of about 1 V/m (volt/meter) over each nest. The latter
value is approximate, the only precise one being 10 dBm. Theoretically, it can be
FIGURE 3 Experimental protocol. The here schematized manipulations were simultaneously
performed on six colonies. EW¼electromagnetic waves (GSM 900 MHz radiation) delivered by a
generator (see the “Material and Methods” section). In the “Results” section, are related all the
results concerning olfactory conditioning ( ) then all those relative to visual conditioning ( ).
FIGURE 4 Ants’ training and testing in the course of their olfactory (A, to fennel) and visual (B, to a
green hollow cube) conditioning. Tests were performed in Y apparatus (which had their own
bottom) positioned on the ants’ foraging area and provided with the element to learn in one branch
(A: pieces of thyme in the left branch; B: a green arch in the right branch). After being tested, each
ant was momentarily kept in a polyacetate cup until 20 ants were tested.
4 M.-C. Cammaerts et al.
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stated that a power density of 10 dBm gives an electromagnetic field of 0.77 V/m
what corresponds to 7.95 £10
24
W/m
2
or 7.95 10
25
mW/cm
2
.
The duration of exposure is detailed in the section “Experimental protocol.”
Briefly, several exposure periods were successively and discontinuously conducted:
the first period lasted four and a half days; the second one, six days; the third one,
one and a half days and the last one, two days.
It must be known that, when it is activated, a typical GSM device, located at a
few hundred meters from a common communication mast (not a booster or a
repeater but a common efficient antennae), emits electromagnetic waves nearly
every 30 s and has a power density of about 2 watts. The power density at
a distance r (in meters) from such a GSM can be calculated using the formula:
P (Watt)/[4 £Pius £(r (m))
2
] with P ¼2 Watts and Pius ¼22/7 ¼3.1416. If
r¼1cm¼0.01 m, P ¼2/4 £22/7 £0.01
2
¼1,590.9 Watts/m
2
¼159.1 mWatts/cm
2
.
However, for short distances (less than the wave length), the formula is not relevant
since the GSM reflects electromagnetic waves, retains energy, and suddenly
transmits it (I.C.N.I.R.P., 1998, and references therein; Wiedemann et al.,
2006). Thus, in the close proximity of a GSM device, the power density is higher
than 1,591 Watts/m
2
and intermittently becomes considerably greater. The
electromagnetic field experimentally generated in the present work had a lower
power density.
It is also of interest to know that the electromagnetic field surrounding
GSM communication masts (again not boosters or repeaters) has a higher
power density than that around a mobile phone, largely varies with the distance
from the masts (like that generated by an activated GSM), and also varies with
the kind of antennae and the countries. The antennae have a power varying
between 2.5 and 320 Watts. However, in several countries, limits have been given
for the electromagnetic fields generated by masts (for instance 3 V/m, 2 V/m in
habited zones). A precise analysis has been made near a common mast
(www.issep.be/open.asp?f ¼/files/ .../CEM%20a%20proximite%20antennes).
One antennae of that mast was set to 37 dBm. The power density of the
electromagnetic field surrounding the mast equaled 5 Watts and that existing at a few
hundred meters from it had a value of 0.250 V/m. Organisms flying near such
common antennae are thus exposed to electromagnetic field similar to that here
experimentally produced.
This information is only given to point out that the electromagnetic field here
experimentally generated on six ant colonies has realistic (and even lower) power
intensity than those usually encountered by living organisms. Since they nest in
ground, grass, or wood, ants however may be less exposed to such electromagnetic
fields than are flying animals (hymenoptera, birds, bats). They are here used as a
model to investigate the effect of natural electromagnetic exposure on flying insects
and animals, in general.
The here used programmed generator always produced the same electro-
magnetic field, that is an electromagnetic field of the same quality and intensity.
Before the start of the present work (¼in the absence of generator), the
electromagnetic field background in the laboratory was very weak, so weak that
it was nearly impossible to phone using a GSM. At that time, the olfactory and the
visual conditioning of M. sabuleti workers had been studied on six never exposed
colonies (see “Introduction”). These six colonies were then maintained in a
room located at 8 m away from the room where the exposure set up was placed.
Two big walls existed between the two rooms. Even when the generator was
switched on, the electromagnetic field surrounding these six never exposed colonies
was very weak.
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Experimental Protocol, Train of Manipulations
The ants were maintained for 16 days without being submitted to GSM 900 MHz
radiation or any experiment. On day 16, the animals were judged to be healthy.
They sufficiently collected meat food and sugared water; they rapidly moved
between nest entrances and food sites; they recuited congeners; they made
trophallaxis; the brood developed; queens were fed; and the low numerous corpses
were transported to cemeteries. Nymphs were precociously appearing in colony 2
(Fig. 3).
The six colonies were simultaneously submitted to GSM 900 MHz radiation and to
olfactory training to fennel. At that time, 20 ants of each colony were tested each day,
at specific times given in Table 1, during 4 1
2days (the period required to obtain the
maximum test score of the population in front of the olfactory cue; Fig. 1). The tested
ants were randomly chosen among the forager populations, made of about 20 30
individuals.
Electromagnetic waves were then turned off during one and a half days. After that,
the ants were simultaneously submitted again to GSM 900 MHz radiation and to
visual training to a green hollow cube. At that time, 20 ants of each colony were
tested at least once a day, at specific times given in Table 2, during six days (the
period required to obtain the maximum test score of the population in front of the
visual cue; Fig. 1)
Electromagnetic waves were then no longer delivered for 30 h. After that, the ants
were submitted to olfactory training to fennel, in the absence of GSM 900 MHz
radiation. Twenty ants of each colony were tested, as indicated above (Table 1),
during 5 days (a laps of time deduced from Fig. 1), i.e., until the ant population’s
score no longer increased.
TABLE 1 Numbers of ants (among 20), belonging to 6 colonies, going to the correct direction in a Y
maze. The ants were trained to an odor (i.e., pieces of fennel) and tested in its presence. Clock and
spent times are given. Mean scores are the mean proportions of correct choices. Statistics are the
results of Wilcoxon non-parametric tests between the test numbers and the six corresponding
control ones. N ¼number of ranks; T ¼sum of the ranks; P ¼probability of occurrence of T under
the assumption of no difference vs. the control; according to Siegel and Castellan (1989). NS ¼not
significant results for P ¼0.05.
Colonies Mean
scores
Statistics
Experiments 123456 NT P
Control 10 9 10 11 10 9 49.2%
Conditioning Under electromagnetic waves
22h30 8 h 9 11 9 10 9 10 48.3% NS
14h30 24 h 10 9 10 9 10 10 48.3% NS
21h30 31 h 9 10 10 9 9 11 46.7% NS
17h30 51 h 9 10 9 8 11 10 47.5% NS
17h30 75 h 9 9 10 10 11 8 47.5% NS
22h30 102 h 10 10 10 8 9 11 47.5% NS
After a 30 h recovery period
9h 9h 13 13 11 13 11 12 60.8% 6 21 0.016
22 h 22 h 14 13 13 12 14 13 65.8% 6 21 0.016
22h30 46.5 h 14 14 15 14 15 15 72.5% 6 21 0.016
22 h 70 h 16 16 17 16 17 16 81.7% 6 21 0.016
22 h 94 h 17 16 16 17 17 16 82.5% 6 21 0.016
13h30 109.5 h 15 16 15 15 16 16 77.5% 6 21 0.016
22 h 118 h 16 16 16 16 15 16 79.2% 6 21 0.016
Again under electromagnetic waves
15 h 16 h 12 13 12 13 12 12 61.7% 6 21 0.016
22h30 23.5 h 11 10 9 10 9 10 49.2% 5 10.5 NS
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Electromagnetic waves were then turned on again, whereby training to fennel
continued: again, 20 ants of each colony were tested at specific times (Table 1)
during one and a half days, a period after which the ant population’s score no longer
decreased.
Then, waves were turned off for 30 h. After that, the ants were submitted to visual
training to a green hollow cube, in the absence of GSM 900 MHz radiation and, once
more, 20 ants of each colony were tested at specific times (Table 2) during 7 days
(i.e., largely after the test score of the population normally no more increased; Fig. 1).
Electromagnetic waves were then turned on again while training to green
continued: again, 20 ants of each colony were tested at specific times during two
days (Table 2), i.e., until the score of the ants’ population no longer changed.
Experimental Material
Ants were collectively olfactory trained by placing, in each tray, small pieces of fennel
around a piece of dead cockroach deposited on a cover glass (Fig 2A,C). They were
collectively visually trained by placing, in each tray, the frame of a green hollow cube
over a piece of dead cockroach deposited on a cover glass (Fig. 2B,D). The hollow
cubes were made of strong green paper (Canson w) and glued exactly like the black
hollow cubes used for studying the ants’ adaptation to light intensity (Cammaerts,
2005) and the green hollow cubes used for defining the kinetics of the ants’ visual
conditioning (Cammaerts et al., in press). The wavelength spectra reflected by the
green paper is given in Cammaerts (2007b) and in Cammaerts and Cammaerts
(2009). Note that it was each time operant conditioning: the ants going by themselves
to the experimental apparatus without any intervention of researchers.
Ants were individually tested (during control and test experiments) in a Y-maze
positioned in the ants’ trays, each colony having its own maze (Fig. 4A,B). The “Ys’”
TABLE 2 Legend identical to that of Table 1 except that the cue used for training and testing the ants
was a visual one, i.e., a green hollow cube.
Colonies Mean
scores
Statistics
Experiments 123456 NT P
Control 10 9 10 11 10 9 49.2%
Conditioning Under electromagnetic waves
15h30 16 h 9 9 9 10 9 8 47.5% NS
15h30 40 h 8 10 10 9 10 9 46.6% NS
14h30 63 h 9 10 10 9 9 10 47.5% NS
14h30 87 h 910889844.2% 6 21 0.016
17 h 113.5 h 9 11 9 10 8 11 48.3% NS
17 h 138.5 h 9 9 10 8 10 10 47.5% NS
After a 30 h recovery period
22 h 23 h 10 10 11 11 11 12 54.2% 4 10 0.06
22 h 47 h 11 12 12 11 11 12 57.5% 5 15 0.03
14 h 63 h 12 11 12 12 13 12 60.8% 6 21 0.016
22 h 71 h 12 11 13 11 14 13 61.7% 6 21 0.016
13h30 86.5 h 12 13 13 13 13 14 63.3% 6 21 0.016
12h30 109.5 h 13 13 13 13 13 13 65.0% 6 21 0.016
15h30 136.5 h 13 13 13 14 13 13 65.8% 6 21 0.016
23h30 168.5 h 13 13 13 13 14 13 65.8% 6 21 0.016
Again under electromagnetic waves
9h30 9 h 11 13 11 10 12 12 57.5% 6 19 0.047
15h30 15 h 11 10 11 11 11 10 53.3% 5 15 0.03
22h30 22 h 11 12 8 10 11 10 51.7% NS
22h30 46 h 10 9 9 9 11 10 48.3% NS
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were built of strong white paper. They had their own bottom and their borders were
covered with a thin strip of talc. They were provided with fennel (olfactory
conditioning) or an arch in strong green paper (visual conditioning) set in one
branch of the Y maze, the left or the right one randomly changed from one
experiment to the other and from a colony to the other. Such Y-mazes are described
and pictured in the article dealing with the ants’ conditioning under normal
condition (Cammaerts et al., in press).
Ant Training
This was made by continuously presenting to the ants either the olfactory or the
visual training apparatus provided with meat food. All the foragers of each used
colony were so continuously submitted to either an olfactory or a visual operant
conditioning. During the training period, the apparatus were relocated once or twice
each day and meat was renewed whenever necessary, but never periodically to avoid
spatial as well as temporal learning M. sabuleti can acquire (Cammaerts, 2004b).
Ant Testing
All the control and test experiments were performed in the Y-apparatus briefly
described above (Experimental material) and shown in Fig. 4. During a control,
the Y was empty. During a test, the Y was provided with the olfactory or the visual
cue with which the ants had been trained. The cue was placed in the left or in the
right arm of the Y, randomly from one experiment to the next and from one colony
to the next.
To conduct a control or a test on a colony, 20 foragers of that colony were
transferred one by one into the Y apparatus, close to the entrance. The ants were not
marked. The 20 tested ants were randomly chosen among the population of foragers
of each colony (20 30 ants per colony). The same ant population was so used for
each experiment though not exactly the same ants were each time tested. Each
transferred ant was observed until it turned, inside of the “Y” at the choice point,
either to the left or to the right, its choice being recorded. Only the first choice was
noted, regardless whether the ant turned back on its own path and independent of
any secondary choice. Then the tested ant was removed from the Y and transferred
into a polyacetate cup whose rim was covered with talc, until 20 congeners were
tested. The same manipulation was performed on each of the six used colonies. Note
that the observations were made by the first author for avoiding, to the co-authors,
healthy problems caused by the exposure.
Quantification of Ant Responses; Statistical Analysis
Each experiment consisted in recording (for each colony) the number of ants turning
to the left and to the right (control) or towards the cue and towards the other
direction (test) in the Y device (Tables 1, 2). The experiments performed on the six
colonies were similarly designed. This enabled calculating the mean proportion of
ants that turned towards the cues (i.e., % of correct responses; Tables 1, 2). Wilcoxon
nonparametric tests (Siegel and Castellan, 1989) were performed between the six
numbers (a number per colony, see the first sentence of this paragraph) of ants
having turned towards the cue during the test and the six corresponding control
numbers. The obtained values at time “x” were thus compared to those at time
“zero” (that is the control values obtained without exposure and, above all, without
training). The ants’ responses were considered as being not significant at P .0.05.
We used a one sided test because we statistically analyzed the ants’ conditioning
score (is it statistically higher than the control one?) and not the effect (initially
unknown) of GSM 900 MHz radiation.
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RESULTS
Association between Food and Olfactory Cue under GSM 900 MHz Radiation
When submitted to olfactory training under normal conditions, M. sabuleti workers
responded to the presented odour with a score of 60% after 6 h of training; the test
score of the population improved to 85% after 3 1
2days. Then, the ants permanently
kept this score despite ongoing training. When the odor was no longer presented, the
ants lost their olfactory memory in about three and a half days (16% in 7 h and the last
13% in 80 h) (Fig. 1).
Under GSM 900M Hz radiation, naive workers of the same species showed a score
of 48.3% after 8 h. The tested ants still presented such a low score (instead of 85%)
after 102 h (i.e., after 4.25 days) (Table 1). Consequently, under the influence of
waves, M.sabuleti workers never could associate the presence of food to that of an
olfactory cue.
Olfactory trained again after a recovery period of 30 h, the ant population
reached a score of 60.8% after 9 h. This score continued to increase during four days,
peaking at 82.5%. Thereafter, even if the olfactory cue was still presented to the ant
population, the final score remained in the range of 7780% (Table 1), i.e., 5% less
than the expected score under normal conditions. This occurred similarly for the six
colonies used. So, obviously, the ants associated food and an olfactory cue less well
after having been exposed to waves rather than those who had never been exposed.
While still trained to fennel and when being at their final score of 77 80%, the
colonies were again submitted to GSM 900 MHz radiation. They then lost 17.5% of
their collective response in 16 h and the last 12% in 23.5 h (Table 1). Thus, when
exposed to electromagnetic communication waves, the ants not only did not
keep their acquired olfactory learning, but also lost it more quickly than when
training ceased under normal conditions.
Association between Food and a Visual Cue, under GSM 900 MHz
Visually trained under normal conditions, M. sabuleti workers first exhibited a
latency period of about 30 h, then acquired 10% of their learning in one day and the
last 18% in about 5 days. After that, though the visual cue was still presented, the ants
went on showing a final score of 75 80%. When the visual cue was removed, under
normal conditions, the ants continued to respond to it for about 30 h, then lost
10% of their response in one day and 5% more in about 3 days. Thereafter, they
permanently kept 10% of their visual memory (Fig. 1).
When visually trained under GSM 900 MHz radiation, the same ant species (but
other, not yet tested workers) presented a collective score of 4647% (instead of 80%)
even after 63 h, a period considerably larger than the usual latency period (Table 2).
The attempt to obtain a better score was extended for a total of 138.5 h (nearly
6 days), but the ants of the six used colonies still failed to acquire any association
between food and the presented visual cue: they exhibited a collective not significant
score of 47.5% after these 6 days (Table 2).
The experimented ants then went through a 30 h recovery period before being re-
submitted to visual training without exposure to waves. They then exhibited a latency
period of about 47 h (.30 h; Tab. 2), acquiring 10% of their association between food
and the visual cue in about 65 h 70 h (.1 day) and the last 5% in about 3 days
(Tab. 2). The training was then maintained, but the ants never reached the expected
normal score of 75% 80%. Therefore, after having been submitted to GSM 900 MHz
radiation for 6 days and having then recovered for 30 h, M. sabuleti workers
presented a deficiency of more than 10% (65% instead of 75 80%) of their ability in
associating food and a visual cue. This occurred similarly for the six colonies used.
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The ants that had acquired some ability in associating food and a visual cue (score
of 65%) were thereafter still maintained under training and simultaneously
re-submitted to GSM 900 MHz radiation. They lost 7% of their performance in 9 h and
all of it in 22 h (Table 2). Consequently, under the influence of waves, previously and
permanently trained ants: (1) forgot their acquired association between food and a
visual cue; (2) forgot more rapidly than when no longer trained under normal
conditions; and (3) kept no visual memory at all, instead of 10% under normal
conditions.
PHYSIOLOGICAL OBSERVATIONS
Twenty years of maintaining and working on M. sabuleti in the laboratory enabled us
to detect six physiological deficiencies in the colonies submitted to electromagnetic
waves (four exposures, ranging from 4 6 days, with a 30 h recovery period in
between). These observations were supported by a comparison with the
physiological state of twenty other laboratory colonies never exposed to wireless
waves.
.The foragers moved slowly, hesitantly, often turning back or stopping instead of
going quickly and directly towards their food sites or their nest entrances.
FIGURE 5 Effects, on an ant colony, of a few days (see Figure 3) exposure to GSM 900 MHz radiation.
A: a never exposed colony; B: an exposed colony. Initially, the colony shown in B was more
populous than that shown in A. The effect of the radiation is obvious. Details are given in the text,
in the “Physiological Observations” section.
10 M.-C. Cammaerts et al.
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.Some ants exhibited locomotors ataxia.
.The level of food intake (pieces of dead cockroaches and sugared water)
decreased during exposure to the waves.
.The larvae present in the nests at the start of the experiment ceased development:
they either remained at the same larval stage or died at the end of the four
exposure periods.
.Nymphs of colony 2 stopped their development into callows; they were found
unchanged or dead after the experiments. During the experimental period, the
brood of all the unexposed colonies developed into callows and/or into imagos.
.About 50 adults per colony and a queen of 1 colony were found dead on the
foraging area at the end of the manipulations. Contrary to the normal scenario,
they were not transported to the colony’s cemetery.
These observations were not quantified nor statistically analyzed since they were
not expected. But we photographed one of the never exposed colonies and one of the
exposed ones (Fig. 5). Before exposure, the latter colony was more populous than the
other one. The effects of GSM 900 Mhz radiation are obvious.
Two months after their exposure to GSM 900 MHz radiation, the ants of the six
colonies appeared to be again in good health, exhibiting normal movement, food
collection, nestmate recruitment, and brood rearing. Of course, they were less
numerous than before the experiments. Obviously, adaptation to electromagnetic
exposure is impossible. Unexpectedly, ovary development occurred in several
workers of the six exposed colonies.
CONCLUSIONS
Based on a knowledge of the acquisition and the loss of the association between food
and an olfactory or a visual cue by the foragers of the ant M. sabuleti (Fig. 1;
Cammaerts et al., in press), the present work shows and quantifies six effects of GSM
900 MHz radiation on such an ability.
(1) Exposed naive workers failed to acquire the ability of associating encountered
cues and the presence of food.
(2) After exposure and a subsequent 30 h recovery period, the ants could associate
food and an olfactory or a visual cue but never reached the expected scores.
Deficiencies of 5% (among 30%) for the olfactory association and of 10% (among
25%) for the visual one were recorded.
(3) While being either olfactorily or visually trained, and when exposed to waves, the
ants having already acquired some association between food and cues lost their
acquisition instead of keeping it unchanged.
(4) The loss of the association between food and an olfactory or a visual cue under
exposure (instead of keeping it: see ‘3.’ here above) was more rapid than in those
ants that were no longer trained in normal experiments (and therefore naturally
lost their acquired association). Olfactory memory vanished in 23.5 h vs. 3 1
2days,
visual one in 22 h vs. 4 days.
(5) Exposed ants entirely lost their ability in using a visual cue instead of
permanently keeping 10% of it (as they did under normal conditions though no
longer being trained).
(6) Exposure seems to affect visual memory more than olfactory memory.
(7) Moreover, six physiological impacts of GSM 900 MHz radiation were observed
(but not quantified because they were unexpected). These impacts concerned
ant movement, feeding and brood development.
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Our Results Lead to Four Comments
(1) There is a chronological order of visible impacts of GSM 900 MHz radiation
on the ants’ conditioning, behavior and physiology. First, learning
performances suffered; then, foragers’ movement on their foraging areas
appeared to be affected; after that, several ant activities deviated from the
normal; at that time, it was subjectively observed that brood rearing suffered;
then larvae and nymphs no longer moulted; finally, unusually large numbers of
workers and larvae died.
(2) Previous ethological work showed that visual memory in ants is more complex
and has more steps (depends on more physiological events) than olfactory
memory. Anatomical works are also in favor of such a difference between
olfactory and visual perception in insects (i.e., Strausfeld, 2009): more nervous
cells are concerned. The present work reveals a more severe impact of
electromagnetic wave exposure on visual vs. olfactory memory, agreeing with an
impact of electromagnetic waves primarily on nerve cells. It should be of interest
to assess insects’ memory in the absence and under the influence of RF
radiation. No rigorous work exist on the subject but informative links can be
found on internet (i.e., http://www.newmediaexplorer.org/sepp/2007/03/06/
millions_of_bees_die_are_electromagnetic_signals_to_blame.htm).
(3) Olfactory conditioning to fennel was actually an olfactory and not a visual
conditioning. It has previously been checked that M. sabuleti workers
conditioned to fennel correctly reacted to aqueous extract of fennel (Cammaerts
and Rachidi, 2009).
(4) Our results and observations suggest that GSM 900 MHz radiation might have a
severe impact on nerve cells. Indeed, efficient association between food and
encountered cues requires a correct functioning of the brain and other nerve
cells. This also applies to the moulting of the larvae and the nymphs, a
physiological event which depends on a correct operation of the pars inter
cerebralis. Our following work on the subject (Cammaerts et al., submitted) and
that of Harst et al. (2006) are in favor of such a hypothesis. Our work on
Paramecium caudatum revealed an impact of GSM 900MHz radiations on the
cellular membrane (Cammaerts et al., 2011).
Recently, Orendaeova et al. (2009) studied the possible risk due to pulsed EMF
(frequency: 2,45 GHz; mean power density: 2.8 mw/cm2) on rat postnatal
neurogenesis, examining the relation with the animal’s age and the duration of
exposure. Newborn and senescent rats were entirely exposed either during 2 days,
4 h/day or during 3 days, 8 h/day. Immunohistochemical changes within nervous
cells were examined: changes in proliferating nervous cell numbers occurred
depending on the animal’s age and the exposure doze. Here we showed a disastrous
impact of EW on an animal’s faculties which depend on its nervous system, i.e. its
olfactory and visual learning and its postnatal development.
The present work deals with acquired behavior. Other experiments focused
on innate behavior (trail following behavior, area marking perception, response to
alarm pheromone, food collection, and nestmate recruitment) and revealed drastic
effect of electromagnetic waves on these natural behaviour (Cammaerts et al.,
submitted).
We cautiously suggest that electromagnetic radiation may have an impact on the
behavior, and more precisely on the orientation behavior, the navigation of animals
which use magnetic field or waves to find their way (migratory birds, bats,
dolphins). Works of Everaert and Bauwens (2007), Nicholls and Racey (2009), as
12 M.-C. Cammaerts et al.
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well as those related in the links http://www.ehow.com/about_6138183_wave-its-
impact-endangered-species.html and http://emfjournal.com/2010/01/19/the-im-
pact-of-magnetic-pulsations-on-humans-and-animals/, are in favor of such
an hypothesis.
Interestingly, at the end of the here related experiments, the overall state of the
six colonies was similar to that of bee colonies suffering from CCD (colony
collapse disorder) (see “Results”). We speculate that the effects of GSM 900 MHz
radiation reported here for ant learning, memorisation and physiological
functions also apply to bee faculties and physiology. The visual memorization,
distance travelled estimation, time evaluation, path integration, and orientation
systems of bees might suffer from exposure to such waves and might, at least
partly, explain their present decay. This hypothesis has in fact been forwarded by
a minority of beekeepers and researchers (e.g., Guillet, 2007; Carlo, 2007).
Although valuable studies reveal insects’ sensitivity to electromagnetic waves (e.g.,
Warnke, 1973; Eskov and Sapozhnikov, 1976; Hsu and Li, 1994; Hsu et al., 2009),
the impact of such exposure on the bees’ life has little been scientifically analyzed
and is still mistaken with or masked by the effect of other factors, among others,
the simultaneous use of several pesticides. The survey made in France on May 16,
2008 (http://www.sciences.gouv.fr/fr/dossiers/bdd/page/3/res/2856/la-dispari-
tion-des-abeilles) reflects this problem. However, recent works obviously showed
the impact of electromagnetic waves on the bees. Harst et al. (2006) studied
unhealthy non thermal effects of electromagnetic wave exposure using bees as a
model and pointed out potential deficiencies in their building as well as returning
behavior. Sharma and Kumar (2010) simply placed two activated GSM inside of
two bee hives and so showed that the bees’ life is negatively influenced by
electromagnetic waves; among others, there was neither honey nor pollen in the
hives after the experiment. Favre (2011, and references therein) revealed that
activated mobile phones induce “piping” in honeybees staying in the hive, a
behavior usually exhibited in disturbed bee colonies or to announce a swarming
process. Recently, Kumar et al. (2011) revealed biochemical changes in honeybee
workers submitted to cell phone radiation.
The effect of GSM 900 MHz radiation on humans has currently become a
problematic subject. Murase’s contributions (2004, 2005, 2006, 2008) are in the
forefront of these studies. Accordingly, molecular mechanisms may be involved in
the impact of electromagnetic waves on organisms. The present results, those of
Cammaerts et al. (2011, submitted), agree with this hypothesis. Though this
approach is still in its early stages, the impact of exposure to communication waves
in animals is becoming increasingly explored as evidenced by several internet links
(e.g., www.scribd.com/doc/6293119/Bees-Birds-And-Mankind-Destroying-nature-
by-electrosmog) as well as by a few scientific works (Stever et al., 2005; Panagopoulos
et al., 2004; Balmori, 2006; Everaert and Bauwens, 2007; Nicholls and Racey, 2009;
Benlaidi and El Kharroussi, 2011).
Lastly, we very cautiously suggest that electromagnetic radiation might be used for
controlling pest insect development. Adequate generators of electromagnetic waves
could, for instance, be switched on, from time to time, to protect flour, seeds,
harvests, and crops against plundering insects.
In the present work, we experimentally demonstrate the effect of 900 MHz
(10 dBm) waves on ant foragers’ ability in using olfactory and visual cues, and
we reveal an impact on their physiology. We speculate about similar effects on
other insects (i.e., bees) and about an impact of EW on the nervous cells
functioning. We cautiously advance some economical-ecological application of
these results.
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ACKNOWLEDGEMENTS
We are very grateful to Drs. R. Cammaerts and S. Patigny (Entomologists) who
helped with the writing of this manuscript. We thank again Dr. S. Patigny for
providing us with several references. Once more, Dr. M. Stachowitsch corrected our
English, and we feel indebted to him. Finally, we very sincerely thank the Editor of
the journal as well as two anonymous referees whose judicious remarks allowed us to
improve our article.
Declaration of interest
The authors report no conflicts of interest. The authors alone are responsible for the
content of and writing of the article.
REFERENCES
Balmori, A. (2006). The incidence of electromagnetic pollution on the amphibian decline: Is this an
important piece of the puzzle? Toxicol. Environm. Chem. 88:287 299.
Balmori, A. (2009). Electromagnetic pollution from phone masts. Effects on wildlife. Pathophysiology 16:
191– 199.
Benlaidi, F. Z., El Kharroussi, M. (2011). Effets des ondes e
´lectromagne
´tiques ge
´ne
´re
´es par le GSM sur la
me
´moire et le comportement chez le rat. http://sites.google.com/site/9drineuro/r%C3%A9sum%
C3%A9s6
Cammaerts, M.-C. (2004a). Some characteristics of the visual perception of the ant Myrmica sabuleti.
Physiol. Entomol. 29:472– 482.
Cammaerts, M.-C. (2004b). Classical conditioning, temporal learning and spatial learning in the ant
Myrmica sabuleti.Biologia 59:243– 256.
Cammaerts, M.-C. (2004c). Visual cue generalisation and spatial conditioning in the ant Myrmica sabuleti.
Biologia 59:257– 271.
Cammaerts, M.-C. (2004d). Operant conditioning in the ant Myrmica sabuleti.Behav. Process. 67:
417– 425.
Cammaerts, M.-C. (2005). Sensitivity and adaptation of Myrmica sabuleti workers (Hymenoptera:
Formicidae) to light. Myrmecol. News 7:77–86.
Cammaerts, M.-C. (2007a). Perspective vision in workers of Myrmica sabuleti MEINERT, 1861
(Hymenoptera: Formicidae). Myrmecol. News 10:21– 26.
Cammaerts, M.-C. (2007b). Colour vision in the ant Myrmica sabuleti MEINERT, 1891 (Hymenoptera:
Formicidae). Myrmecol. News 10:41– 50.
Cammaerts, M.-C. (2008). Visual discrimination of cues differing as for their number of elements, their
shape or their orientation, by the ant Myrmica sabuleti.Biologia 63:11691180.
Cammaerts, M.-C., Cammaerts, D. (2009). Light thresholds for colour vision in the workers of the ant
Myrmica sabuleti (Hymenoptera: Formicidae). Belg. J. Zool. 138:40– 49.
Cammaerts, M.-C., Debeir, O., Cammaerts, R. (2011). Changes in Paramecium caudatum (Protozoa) near a
switched-on GSM telephone. Electromagn. Biol. Med. 30:57–66.
Cammaerts, M.-C., Lambert, A. (2009). Maze negotiation by a myrmicine ant (Hymenoptera: Formicidae).
Myrmecol. News 12:41– 49.
Cammaerts, M.-C., Rachidi, Z. (2009). Olfactive conditioning and use of visual and odorous cues for
movement in the ant Myrmica sabuleti (Hymenoptera, Formicidae). Myrmecol. News 12:117– 127.
Cammaerts, M.-C., Rachidi, Z., Bellens, F., et al. Food collection and response to pheromones in an ant
species exposed to electromagnetic radiation. Belg. J. Zool. submitted.
Cammaerts, M.-C., Rachidi, Z., Cammaerts, D. (2011). Collective operant conditioning and circadian
rhythms in the ant Myrmica sabuleti (Hymenoptera, Formicidae). Bull. Soc. R. Ent. B. 147.
Carlo, G. L. (2007). He
´catombe des abeilles: e
´tude d’un lien avec la pollution e
´lectromagne
´tique.
www.noe.org/fr/hcatombe-des-abeilles-tude-d-un-lien-avec-pollution-lectromgntique-t2i3477p1.html
Eskov, E. K., Sapozhnikov, A. M. (1976). Mechanisms of generation and perception of electric fields by
honey bees. Biophysik 21:1097–1102.
Everaert, J., Bauwens, D. (2007). Un effet possible des radiations e
´lectromagne
´tiques des stations de base
de te
´le
´phonie mobile sur le nombre de moineaux domestiques (Passer domesticus). Electromagn. Biol.
Med. 26:63– 72.
Favre, D. (2011). Mobile phone-induced honeybee worker piping. Apidologie 42:270-279.
14 M.-C. Cammaerts et al.
Electromagnetic Biology and Medicine
Electromagn Biol Med Downloaded from informahealthcare.com by Dr. Henry Lai on 01/30/12
For personal use only.
Gould, J. L. (1982). Ethology. The Mechanisms and Evolution of Behavior. Princeton University.
Department of Biology. WW Norton et Company. New York (10 110), London (WC1B 3NU), 544 pp.
Guillet, D. (2007). Requiem pour nos abeilles. www.sante
´publique-editions.fr/objets/AbeillesGuillet2.pdf
Harst, W., Kuhn, J., Stever, H. (2006). Can electromagnetique exposure cause a change in behaviour?
Studying possible non-thermal influences on honey bees- An approach within the frame work of
Educational Informatics. Acta Systematica – IIAS Intern. J. 6:1 6.
Hsu, C.-Y., Li, C.-W. (1994). Magnetoreception in Honeybees. Sci. Mag. 265:9597.
Hsu, C.-Y., Ko, F.-Y., Li, C.-W., et al. (2009). Magnetoreception System in Honeybees (Apismellifera).
I.C.N.I.R.P.(1998). Guidelined for limiting exposur to time-varying electric, magnetic and electromagnetic
fields (up to 300 GHz). Health Phys. 74:404 522.
Kumar, N. R., Sangwan, S., Badotra, P. (2011). Exposure to cell phone radiations produces biochemical
changes in worker honey bees. Toxicol. Int. 18:70 72.
Murase, M. (2004). Proceedings of the first meeting on electromagnetic fields and their biological effects.
Bussei Kenkyu Kyoto 82:45–192.
Murase, M. (2005). Proceedings of the second meeting on electromagnetic fields and their biological
effects: towards the investigation of molecular mechanisms. Bussei Kenkyu Kyoto 85:223 362.
Murase, M. (2006). Proceedings of the third meeting on Electromagnetic fields and their biological effects:
molecular mechanisms and total evaluation. Bussei Kenkyu Kyoto 86:621730.
Murase, M. (2008). Environmental pollution and health: an interdisciplinary study of the bioeffects of
electromagnetic fields. SANSAI Environ. J. Glob. Commun. Kyoto Univ. 3:1 35 http://hdl.handle.net/
2433/49793
Nicholls, B., Racey, P. A. (2009). The aversive effect of electromagnetic radiation on foraging bats A
possible means of discouraging bats from approaching wind turbines. PLoSOne4:e6246.
Orendaeova, J., Raeekova, E., Orendae, M., et al. (2009). Immunohistolochemu
`ical study of postnatal
neurogenesis after whole-body exposure to electromagnetic fields: evaluation of age- and dose- related
changes in rats. Zeit. Cell Mol. Neurobiol. 29:981990.
Panagopoulos, D. J., Karabarbounis, A., Margaritis, L. H. (2004). Effect of GSM 900-MHz mobile phone
radiation on the reproductive capacity of Drosophila melanogaster.Electromagn. Biol. Med. 23:2943.
Sharma, V. P., Kumar, N. R. (2010). Changes in honeybee behavior and biology under the influence of
cellphone radiations. Curr. Sci. 98:1376– 1378.
Siegel, S., Castellan, N. J. (1989). Nonparametric Statistics for the Behavioural Sciences. Singapore:
McGraw-Hill Book Company.
Stever, H., Kuhn, J., Otten, C., et al. (2005). Verhaltensanderung unter elektromagnetisher exposition.
Pilotstudie 2005: Agbi (Arbeitsgruppe Bildungsinformatik). Inst fur Mathematik, univ. Koblenz-Landau.
Strausfeld, N. J. (2009). Brain organization and the origin of insects: an assessment. Proc. Roy. Soc. Belg.
Warnke, U. (1973). Physikalisch-physiologishe Grundlagen zur luftelektrisch bedingten “Wetterfu
¨hligkeit”
der Honigbiene (Apis mellifica). Diss. Saarbru
¨cken 276:1029– 1937
Wiedemann, P. M., Thalmann, A. T., Grutsch, M. A., et al. (2006). The impact of precautionary measures
and the disclosure of scientific uncertainty of EMF risk perception and trust. J. Risk Res. 9:361 372.
Electromagnetic Waves Inhibit Learning 15
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... Other authors demonstrate how changes of low intensity in the normal local magnetic field values affect the behaviour of workers of three magnetosensitive ant species, inducing significant changes in their foraging activities (Pereira et al., 2019). Belgian researchers experimentally demonstrated the effect of 900-MHz electromagnetic waves on ant olfactory and visual learning, revealing an impact on their physiology (Cammaerts et al., 2012). The ants' speed of movement was immediately altered by the presence of electromagnetic waves (Cammaerts and Johansson, 2014). ...
... The ants' speed of movement was immediately altered by the presence of electromagnetic waves (Cammaerts and Johansson, 2014). These authors state that electromagnetic radiation affects the behaviour and physiology of social insects, and such results provide convincing evidence of a negative impact of electromagnetic waves on insects, at least on those whose life depends on communication and memory (Cammaerts et al., 2012). Wireless technology has negative impacts on living organisms; ants react quickly to the existence of electromagnetic waves in their environment, and bees may behave abnormally when exposed to EMFs generated by GSM masts (Cammaerts et al., 2013). ...
... Regarding the colony collapse disorder (CCD) observed in honeybee colonies around the world, several authors consider that EMR exposure provides a better explanation than other theories (Sainudeen Sahib, 2011;Cammaerts et al., 2012). Several authors warn that the massive amount of radiation produced by mobile phones and towers disturbs the navigational skills of honeybees, preventing them from returning to their hives (Warnke, 2009;Sainudeen Sahib, 2011). ...
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... Examining effects of manmade electromagnetism on ants revealed that these insects could be used as biological models. 1 Indeed, physiology and ethology are similar in most animals 2 and research is generally firstly made on animals as models (e.g. fruit flies, cockroaches, bees, mice, monkeys) then on humans. ...
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Since 2012, we used ants as models for examining the effects of products used by humans. Here, we summarize our seven last studies which concerned green clay, glucosamine, sildenafil, a homeopathic drug, as well as diclofenac, meloxicam and etoricoxib, three anti–inflammatory drugs. Green clay appeared to be an excellent product without adverse effects. In humans, it allows reducing gastric hyperacidity and should thus be used instead of aluminum hydroxide or calcium + magnesium carbonates which present adverse effects. Glucosamine was also safe. It only increased the ants’ locomotion and this effect might explain, at least partly, its efficiency. Sildenafil has many adverse effects, the cause of which being probably a decrease of sensitive perception. Such an impact may result from the activity of sildenafil: it inhibits phosphodiesterases and increases amounts of cGMP and cAMP. The homeopathic drug Ignatia amara, used for decreasing stress symptoms, had no adverse effects and unexpectedly reduced the ants’ state of stress. Even if its functioning stays unknown, this drug could help stressed persons. Diclofenac had several adverse effects and may lead to dependence; meloxicam had far less adverse effects and did not lead to dependence; etoricoxib had some adverse effects and did not lead to dependence. Obviously, meloxicam was the safest of the three anti–inflammatory drugs. Experimentation on ants can thus inform practitioners and pharmacists on potential harmful effects of products before providing them to humans.
... The exposure of this band as an electromagnetic field is the daily routine of humans and other living organisms due to the increment of the daily usage of mobile phones and other systems using this band. So far the effects of GSM radiation on the behavior of different organisms including bees and ants (Cammaerts et al. 2012;Odemer and Odemer 2019) as well as on the inhibition effects of pathogenic bacteria were reported (Taheri et al. 2017). More studies are required to understand potential effects of GSM 1800 radiation on starter bacteria and their metabolite formation including EPS production. ...
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In this study, the effects of GSM 1800 band radiation on composition, structure and bioactivity of exopolysaccharides (EPSs) produced by Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus were determined. For this, GSM 1800 band radiation was applied to both cultures and characteristics of EPSs extracted from the control groups (K) and the radiation stressed groups (R) were determined. An alteration in the chemical composition of the EPSs was observed and EPS production levels and molecular weights of the EPSs increased following the GSM 1800 band radiation application. Alterations in the functional groups, thermal and morphological characteristics of EPSs following the GSM 1800 band radiation application were confirmed by FTIR, TGA and SEM analysis, respectively. Importantly no alterations in the antioxidant and antibacterial activity of the EPSs were observed following the radiation application. These results suggested the effects of the GSM radiation on final characteristics of EPSs from yogurt starter cultures.
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Ambient levels of nonionizing electromagnetic fields (EMF) have risen sharply in the last five decades to become a ubiquitous, continuous, biologically active environmental pollutant, even in rural and remote areas. Many species of flora and fauna, because of unique physiologies and habitats, are sensitive to exogenous EMF in ways that surpass human reactivity. This can lead to complex endogenous reactions that are highly variable, largely unseen, and a possible contributing factor in species extinctions, sometimes localized. Non-human magnetoreception mechanisms are explored. Numerous studies across all frequencies and taxa indicate that current low-level anthropogenic EMF can have myriad adverse and synergistic effects, including on orientation and migration, food finding, reproduction, mating, nest and den building, territorial maintenance and defense, and on vitality, longevity and survivorship itself. Effects have been observed in mammals such as bats, cervids, cetaceans, and pinnipeds among others, and on birds, insects, amphibians, reptiles, microbes and many species of flora. Cyto- and geno-toxic effects have long been observed in laboratory research on animal models that can be extrapolated to wildlife. Unusual multi-system mechanisms can come into play with non-human species — including in aquatic environments — that rely on the Earth’s natural geomagnetic fields for critical life-sustaining information. Part 2 of this 3-part series includes four online supplement tables of effects seen in animals from both ELF and RFR at vanishingly low intensities. Taken as a whole, this indicates enough information to raise concerns about ambient exposures to nonionizing radiation at ecosystem levels. Wildlife loss is often unseen and undocumented until tipping points are reached. It is time to recognize ambient EMF as a novel form of pollution and develop rules at regulatory agencies that designate air as ‘habitat’ so EMF can be regulated like other pollutants. Long-term chronic low-level EMF exposure standards, which do not now exist, should be set accordingly for wildlife, and environmental laws should be strictly enforced — a subject explored in Part 3.
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This study evaluates the impact on risk perception and trust in public health protection resulting from disclosure of information about implementation of precautionary measures and from the disclosure of scientific uncertainty in the area of mobile telephony. Based on an experimental design, the study supports our recent findings (Wiedemann and Schütz, 2005) that precautionary measures may trigger concerns and amplify EMF‐related risk perceptions. Furthermore, our present data once again indicates that information about the implementation of precautionary measures has no positive effect on trust in public health protection. These results, contrary to common expectations, should be considered in decisions about precautionary measures. Risk managers who intend to implement precautionary measures merely as a means for reassuring the public will probably fail. Indeed, even if precautionary measures are justified from a public health perspective, it seems prudent to anticipate the possibly countervailing effects of such measures on the public. This leads to two important challenges for risk communication, first to clarify the difference between hazard and risk and, second, to help avoid such unwanted effects by designing better communication about precautionary measures.
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Previous studies suggested that workers of the ant species Myrmica sabuleti have different light thresholds for distin- guishing different colours. Here we assess these thresholds and find that the light thresholds required to distinguish colours from grey are lower than those necessary to discriminate between two colours. The two thresholds are somewhat lower for ants trained under low versus high light intensity. In every case, the ants' threshold decreases from red to violet. All these thresholds are lower than those required for perceiving shapes. The visual system of workers of M. sabuleti under very low light intensity may thus con- sist of discriminating only coloured spots from grey and under slightly higher light intensity, differently coloured elements where the eyes are used in superposition mode. Under high light intensity, these ants see (although not sharply) shapes and lines, using their eyes in apposition mode. Moreover, workers of this species demonstrated their best colour discrimination in seeing the colours yellow and blue under high light intensity, and green and violet under low light intensity. Therefore, these ants' visual system may be adapted to the quantitative and qualitative variations in natural light during the day.
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Since classical conditioning and spatial learning are possible in the ant Myrmica sabuleti, we aimed to investigate the possibility of spatial conditioning in this ant species. First we demonstrated that workers can distinguish between different cues. Second we used these cues as conditioned stimuli (CS) to try to obtain spatial conditioning. Reinforcing experiments were performed according to three methods: (i) repeatedly alternating presentations of two distinct CS, each one associated with an unconditioned stimulus (UCS) located at a precise place; (ii) repeatedly alternating presentations of two CS, each one associated with a UCS located at a precise place and a "non-reward" at the opposite place; (iii) successive presentations of two CS, each one associated with a UCS located at a precise place. The last method was repeated so that the order of presentation of each CS was alternated. Spatial conditioning was obtained with each of the three methods: the proportion of spatially conditioned ants was 43% (first method), 35% (second method) and 45% (third method). With the first method, spatial conditioning could be shown only on the basis of this proportion. With the second method, spatial conditioning was suggested on the basis of the numbers of ants responding to the CS. With the third method, spatial conditioning was obvious on the basis of the numbers of responding ants. The ants' conditioning and spatial conditioning extinguished in three (first method), four (second method) and five (third method) experiments of extinction. The third method showed that conditioning to the first CS presented was always stronger than that to the second CS used. In short, (i) spatial conditioning exists in Myrmica sabuleti, which might explain the ants' use of cues for orienting themselves; (ii) a first conditioning is stronger than the following which might explain the ants' route fidelity.
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My previous work demonstrated that Myrmica sabuleti MEINERT, 1861 workers see their environment with perspec-tive. The stereovision of this species, which has rather small and laterally located eyes, cannot be explained by bino-cular vision. In the present study I show that – under UV light alone or yellow light alone – these ants do not perceive perspective, while under combined yellow and UV light as well as under natural light they perfectly perceive per-spective. Motion parallax is probably not the mechanism giving M. sabuleti workers depth perception. Perspective detection in these ants is also not based on visible overall length, this hasbeen experimentally checked. Therefore, I suggest that M. sabuleti workers see their environment with some perspective based on their sensitivity both to vis-ible light (or perhaps long wavelengths) and to UV light (or perhaps short wavelengths). This interpretation requires experimental confirmation.
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Olfactive conditioning was achieved in the ant Myrmica sabuleti MEINERT, 1861 using either meat or sugared water as a reward (P < 0.016). This conditioning was superior using meat as a reward as had been the case in visual operant conditioning previously obtained in that species. Differential olfactive conditioning was also achieved in M. sabuleti using sugared water as a reward (0.031 < P < 0.016). This result suggests that these ants may use odours as cues to nego-tiate their way. Experiments were thus conducted in mazes provided with learned odours: the ants could negotiate their way (P < 0.001). They could also do so with alternative presence of visual and odorous cues (P < 0.001). Ants were then confronted with visual and odorous cues either in agreement or competitively presented. Myrmica sabuleti workers responded primarily to learned odours and secondarily to learned visual cues (correct odours + wrong visual cues: P < 0.001, wrong odours + correct visual cues: P < 0.01); the result for wrong odours + correct visual cues was still significant because the ants appeared to rapidly stop responding to learned odours when these elements fail to help them navigate.
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CAMMAERTS, M.-C., Classical conditioning, temporal learning and spatial learning in the ant Myrmica sabuleti. Biologia, Bratislava, 59: 243|256, 2004; ISSN 0006-3088. After working for 30 years on ethological, physiological and chemical prob- lems concerning ants, we predicted that conditioning and/or learning may be obtained in these animals. Therefore, the rst thing we made was to test three types of learning in foragers of the ant Myrmica sabuleti :t emporal learning, spatial learning and classical conditioning. Workers were able to perform tem- poral learning of a particular period of the day after a 12-day training period. This initial learning extinguished after 3 days in the absence of food. A second subsequent temporal learning was more rapid and more ecient. Moreover, its extinction took longer. The workers were also able to exhibit spatial learning of a feeding place precisely located in their foraging area. After extinction of this rst spatial learning in a few experiments in the absence of food, a second subsequent learning performed under the same training conditions was more rapid and generally more ecient, and its extinction took a little longer, as previously found for temporal learning. Classical conditioning was possible in M. sabuleti, when the conditioned stimuli (visual: green triangle; olfactive: onion) were presented either a few minutes before, just before, or at the same time as the unconditioned stimulus (liquid sugared food). Such conditioning failed if the conditioned stimulus was presented, then removed, 15 min before the unconditioned stimulus, or, if it was presented after the unconditioned stimulus. In the three cases where conditioning occurred, the ants' responses extinguished after a few experiments. Second subsequent conditionings were more rapid and generally more ecient, and extinguished more slowly. The workers discriminated yellow and blue from green, but generalised the re- sponse they gave to a triangle, to a square and a rectangle; they generalised their response to onion, to leek and garlic, but discriminated cabbage and Belgian endive from onion. Thus, in summary, classical conditioning as well as temporal and spatial learning can be obtained in the ant M. sabuleti using precise experimental protocols. This discovery allows us to go further and to study, in the same species, spatial conditioning, visual perception, and operant conditioning (works respectively published and in press).
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Since classical conditioning and spatial learning are possible in the ant Myr- mica sabuleti, we aimed to investigate the possibility of spatial conditioning in this ant species. First we demonstrated that workers can distinguish between dierent cues. Second we used these cues as conditioned stimuli (CS) to try to obtain spatial conditioning. Reinforcing experiments were performed accord- ing to three methods: (i) repeatedly alternating presentations of two distinct CS, each one associated with an unconditioned stimulus (UCS) located at a precise place; (ii) repeatedly alternating presentations of two CS, each one associated with a UCS located at a precise place and a \non-reward" at the opposite place; (iii) successive presentations of two CS, each one associated with a UCS located at a precise place. The last method was repeated so that the order of presentation of each CS was alternated. Spatial conditioning was obtained with each of the three methods: the proportion of spatially condi- tioned ants was 43% (rst method), 35% (second method) and 45% (third method). With the rst method, spatial conditioning could be shown only on the basis of this proportion. With the second method, spatial conditioning was suggested on the basis of the numbers of ants responding to the CS. With the third method, spatial conditioning was obvious on the basis of the numbers of responding ants. The ants' conditioning and spatial conditioning extinguished in three (rst method), four (second method) and ve (third method) exper- iments of extinction. The third method showed that conditioning to the rst CS presented was always stronger than that to the second CS used. In short, (i) spatial conditioning exists in Myrmica sabuleti, which might explain the ants' use of cues for orienting themselves; (ii) a rst conditioning is stronger than the following which might explain the ants' route delity.